I'm staring at the schematics and it occurs to me that the speakers are also inductors. If I ran a line array of many, many drivers in parallel, the overall impedance would probably match that of the Plitron. Could I remove the transformer and use the speakers as the inductor? I know it's kinda weird. But the spark of inspiration is there. Is that all it is?

If the center tap is necessary, I suppose one could use speakers with dual voice coils.

Kind regards to the brains out there...

John Inlow

I'll try this experiment with my next amp before placing it in the chassis with its brother. I'm sure I have a cheap dual-voice-coil pioneer speaker out there in the garage... if not, I could center tap two standard drivers run out of phase? To phase or not to phase, that is the

So... here's my two-bit question: how do I sum the stereo inputs to create mono?

Sorry if this sounds dumb, but the sound is absolutely amazing, and I'd like to explore further. I'm listening to an old Patsy Cline/ Jim Reeves cd and it sounds like it was recorded with modern technology. They certainly used too much reverb back then. Other than that the voice is crystal clear.

The two winding idea only helps the transformer saturation. The oposite windings make a feild that opposes the other, for the bias current, so there for all intents and purposes, is no field. Except for the audio signal, which are opposite currents. But, as Nobody Special said, you can't have that 2 Amps bias current going through the light as possible voice coil
If one were to use this idea with a big xfmr, is the 1H Pri L the target? Is that obtainable from a manufactured, off the shelf, component? Do they give the Pri L specs on these big toriods we're using in the supply?? I suppose I will drag my 50V supply to work and measure the Pri L for starters... Actually, at work, I have some connections I had not thought about. I know people who wind inductors, Hmmm... JSOZ-T

I kept focusing on the cancellation effects and forgot about the bias current and the bias transistor. If I were a pro, I'd be wearing egg on my face

Thanks for taking the time to post. Please keep us informed on you inductor quest. I just received an inductance meter from ebay. I just have to connect a nine volt battery and I can test the 1000v/a plitron for inductance.

I performed an inductance test on my plitron 1000v/a. Results are 172.7mH and 172.4mH on the dual 110v inputs

That's really not so tough to transfer into air chokes. Is 4.66 ohms resistance per choke too much. I'm looking at 16 gauge wire. This yields a choke with the dimensions of 1" dia. core, 1" width, 6.89" outer dia. It will take two of these babies per mono-block. They could be placed side by side and connected like a center tapped plitron to cancel magnetics. Or is this totally unnecessary.

Well I like the idea. It appears a "Tube Like" sound approaching very good measured specs is very possible with the cascoded JFET. I'm thinking a SOZ style thing with the JFET. With the transformer I like the fact that the load efficiency and performance is better without the use of N.P.s I.P or monster resistors. A bridging or differential mode operation provides even more performance enhancement and power. Most tube power amps had a transformer and it must have contributed an inductor non linearity that was more plesent a sound than many of the modern designs. Otherwise, tubes would be gone from audio??? We would not be chasing simple, single ended, single stage amps that are the closest topologies to the tube designs. It will be interesting where all this JFET DIY goes... I think a cool preamp design will be available soon too from the sound of things.
Anyway, I'ld just like to get more of a handle how to design in this thing or select an optimum of the available??? If I want 8 ohms at 5Hz that's .25H right? And it goes up from there... I'm guessing that would be the largest inductor I could get anyway. I like to work this stuff out on Pspice before I buiild. Maybe after the current project I will try some of this coupled centertapped inductor loading stuff on the simulator...